LT1739
Dual 500mA, 200MHz
xDSL Line Driver Amplifier
FEATURES
s
s
DESCRIPTIO
s
s
s
s
s
s
s
s
s
3mm
×
4mm High Power DFN Package
Exceeds All Requirements For Full Rate,
Downstream ADSL Line Drivers
±500mA
Minimum I
OUT
±11.1V
Output Swing, V
S
=
±12V,
R
L
= 100Ω
±10.9V
Output Swing, V
S
=
±12V,
I
L
= 250mA
Low Distortion: – 82dBc at 1MHz, 2V
P-P
Into 50Ω
Power Saving Adjustable Supply Current
Power Enhanced TSSOP-20 Small Footprint Package
200MHz Gain Bandwidth
600V/µs Slew Rate
Specified at
±12V
and
±5V
The LT
®
1739 is a 500mA minimum output current, dual op
amp with outstanding distortion performance. The ampli-
fiers are gain-of-ten stable, but can be easily compensated
for lower gains. The extended output swing allows for
lower supply rails to reduce system power. Supply current
is set with an external resistor to optimize power dissipa-
tion. The LT1739 features balanced, high impedance in-
puts with low input bias current and input offset voltage.
Active termination is easily implemented for further sys-
tem power reduction. Short-circuit protection and thermal
shutdown insure the device’s ruggedness.
The outputs drive a 100Ω load to
±11.1V
with
±12V
supplies, and
±10.9V
with a 250mA load. The LT1739 is a
pin-for-pin replacement for the LT1794 in xDSL line driver
applications and requires no circuit changes.
The LT1739 is available in the very small, thermally
enhanced, 3mm
×
4mm DFN package or a 20-lead TSSOP
for maximum port density in central office line driver
applications. For a dual version of the LT1739, see the
LT6301 data sheet.
, LTC and LT are registered trademarks of Linear Technology Corporation.
APPLICATIO S
s
s
s
s
s
High Density ADSL Central Office Line Drivers
High Efficiency ADSL, HDSL2, G.lite,
SHDSL Line Drivers
Buffers
Test Equipment Amplifiers
Cable Drivers
TYPICAL APPLICATIO
12V
R
BIAS
24.9k
SHDN
High Efficiency
±12V
Supply ADSL Central Office Line Driver
3mm
×
4mm DFN Package
Bottom View
12.7Ω
EXPOSED
THERMAL
PAD
+IN
+
1/2
LT1739
–
1k
110Ω
1000pF
1:2*
0.8
mm
•
•
100Ω
110Ω
1k
1739 TA01
173
9T
A0
2
–
1/2
LT1739
–IN
12.7Ω
SHDNREF
*COILCRAFT X8390-A OR EQUIVALENT
I
SUPPLY
= 10mA PER AMPLIFIER
WITH R
BIAS
= 24.9k
+
–12V
U
3m
m
m
4m
1739fas, sn1739
U
U
1
LT1739
ABSOLUTE
MAXIMUM
RATINGS
Supply Voltage (V
+
to V
–
) .................................
±13.5V
Input Current .....................................................
±10mA
Output Short-Circuit Duration (Note 2) ........... Indefinite
Operating Temperature Range ............... – 40°C to 85°C
Specified Temperature Range (Note 3) .. – 40°C to 85°C
PACKAGE/ORDER INFORMATION
TOP VIEW
V
–
1
NC 2
–IN 3
+IN 4
SHDN 5
SHDNREF 6
+IN 7
–IN 8
NC 9
V
–
10
20 V
–
19 NC
18 OUT
17 V
+
16 NC
15 NC
14 V
+
13 OUT
12 NC
11 V
–
UE12 PACKAGE
12-LEAD (4mm
×
3mm) PLASTIC DFN
T
JMAX
= 125°C,
θ
JA
= 60°C/W,
θ
JC
= 3°C/W (Note 4)
UNDERSIDE METAL CONNECTED TO V
–
ORDER PART
NUMBER
TOP VIEW
LT1739CFE
LT1739IFE
FE PACKAGE
20-LEAD PLASTIC TSSOP
T
JMAX
= 150°C,
θ
JA
= 40°C/W,
θ
JC
= 3°C/W (Note 4)
UNDERSIDE METAL CONNECTED TO V
–
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
The
q
denotes the specifications which apply over the full specified temperature range, otherwise specifications are at T
A
= 25°C.
V
CM
= 0V, pulse tested,
±5V ≤
V
S
≤ ±12V,
V
SHDNREF
= 0V, R
BIAS
= 24.9k between V
+
and SHDN unless otherwise noted. (Note 3)
SYMBOL
V
OS
PARAMETER
Input Offset Voltage
q
CONDITIONS
Input Offset Voltage Matching
q
Input Offset Voltage Drift
I
OS
I
B
Input Offset Current
Input Bias Current
q
Input Bias Current Matching
q
e
n
i
n
Input Noise Voltage Density
Input Noise Current Density
f = 10kHz
f = 10kHz
2
U
U
W
W W
U
W
(Note 1)
Junction Temperature
FE Package ....................................................... 150°C
UE Package ...................................................... 125°C
Storage Temperature Range
FE Package ....................................... – 65°C to 150°C
UE Package ...................................... – 65°C to 125°C
Lead Temperature (Soldering, 10 sec).................. 300°C
ORDER PART
NUMBER
–IN A
+IN A
SHDN
SHDNREF
+IN B
–IN B
1
2
3
4
5
6
12 V
–
11 OUT A
10 V
+
9
8
7
V
+
OUT B
V
–
LT1739CUE
LT1739IUE
UE PART
MARKING
1739
1739I
MIN
TYP
1
0.3
MAX
5.0
7.5
5.0
7.5
500
800
±4
±6
500
800
UNITS
mV
mV
mV
mV
µV/°C
nA
nA
µA
µA
nA
nA
nV/√Hz
pA/√Hz
1739fas, sn1739
q
q
10
100
±0.1
100
8
0.8
LT1739
ELECTRICAL CHARACTERISTICS
The
q
denotes the specifications which apply over the full specified temperature range, otherwise specifications are at T
A
= 25°C.
V
CM
= 0V, pulse tested,
±5V ≤
V
S
≤ ±12V,
V
SHDNREF
= 0V, R
BIAS
= 24.9k between V
+
and SHDN unless otherwise noted. (Note 3)
SYMBOL
R
IN
C
IN
PARAMETER
Input Resistance
Input Capacitance
Input Voltage Range (Positive)
Input Voltage Range (Negative)
CMRR
PSRR
A
VOL
Common Mode Rejection Ratio
Power Supply Rejection Ratio
Large-Signal Voltage Gain (Note 8)
(Note 5)
(Note 5)
V
CM
= (V
+
– 2V) to (V
–
+ 2V)
q
q
q
CONDITIONS
V
CM
= (V
+
– 2V) to (V
–
+ 2V)
Differential
q
MIN
5
TYP
50
6.5
3
V
+
– 1
V
–
+ 1
83
88
76
70
11.1
10.9
4.0
3.9
1200
10
8
6
4
MAX
UNITS
MΩ
MΩ
pF
V
V
dB
dB
dB
dB
dB
dB
dB
dB
±V
±V
±V
±V
±V
±V
±V
±V
mA
V
+
–2
V
–
+
2
74
66
74
66
63
57
60
54
10.9
10.7
10.6
10.4
3.7
3.5
3.6
3.4
500
8.0
6.7
V
S
=
±4V
to
±12V
q
V
S
=
±12V,
V
OUT
=
±10V,
R
L
= 40Ω
q
V
S
=
±5V,
V
OUT
=
±3V,
R
L
= 25Ω
q
V
OUT
Output Swing (Note 8)
V
S
=
±12V,
R
L
= 100Ω
q
V
S
=
±12V,
I
L
= 250mA
q
V
S
=
±5V,
R
L
= 25Ω
q
V
S
=
±5V,
I
L
= 250mA
q
I
OUT
I
S
Maximum Output Current (Note 8)
Supply Current per Amplifier
V
S
=
±12V,
R
L
= 1Ω
V
S
=
±12V,
R
BIAS
= 24.9k (Note 6)
V
S
=
±12V,
R
BIAS
= 32.4k (Note 6)
V
S
=
±12V,
R
BIAS
= 43.2k (Note 6)
V
S
=
±12V,
R
BIAS
= 66.5k (Note 6)
V
S
=
±5V,
R
BIAS
= 24.9k (Note 6)
q
q
13.5
15.0
mA
mA
mA
mA
mA
mA
mA
mA
mA
dB
dB
V/µs
V/µs
dBc
dBc
MHz
2.2
1.8
3.4
0.1
0.3
5.0
5.8
1
1
Supply Current in Shutdown
Output Leakage in Shutdown
Channel Separation (Note 8)
SR
HD2
HD3
GBW
Slew Rate
Differential 2nd Harmonic Distortion
Differential 3rd Harmonic Distortion
Gain Bandwidth
V
SHDN
= 0.4V
V
SHDN
= 0.4V
V
S
=
±12V,
V
OUT
=
±10V,
R
L
= 40Ω
q
80
77
300
100
110
600
200
– 85
– 82
200
V
S
=
±12V,
A
V
= – 10, (Note 7)
V
S
=
±5V,
A
V
= –10, (Note 7)
V
S
=
±12V,
A
V
= 10, 2V
P-P
, R
L
= 50Ω, 1MHz
V
S
=
±12V,
A
V
= 10, 2V
P-P
, R
L
= 50Ω, 1MHz
f = 1MHz
Note 1:
Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2:
Applies to short circuits to ground only. A short circuit between
the output and either supply may permanently damage the part when
operated on supplies greater than
±10V.
Note 3:
The LT1739C is guaranteed to meet specified performance from
0°C to 85°C and is designed, characterized and expected to meet these
extended temperature limits, but is not tested at – 40°C. The LT1739I is
guaranteed to meet the extended temperature limits.
Note 4:
Thermal resistance varies depending upon the amount of PC board
metal attached to the device and rate of air flow over the device. If the
maximum dissipation of the package is exceeded, the device will go into
thermal shutdown and be protected.
Note 5:
Guaranteed by the CMRR tests.
Note 6:
R
BIAS
is connected between V
+
and the SHDN pin, with the
SHDNREF pin grounded.
Note 7:
Slew rate is measured at
±5V
on a
±10V
output signal while
operating on
±12V
supplies and
±1V
on a
±3V
output signal while
operating on
±5V
supplies.
Note 8:
This parameter of the LT1739CUE/LT1739IUE is 100% tested at
room temperature, but is not tested at –40°C, 0°C or 85°C.
1739fas, sn1739
3
LT1739
TYPICAL PERFOR A CE CHARACTERISTICS
Supply Current
vs Ambient Temperature
V
S
=
±12V
14 R
BIAS
= 24.9k TO SHDN
V
SHDNREF
= 0V
13
12
11
10
9
8
7
6
5
–50
–30
–10 10
30
50
TEMPERATURE (°C)
70
90
15
V
+
–0.5
COMMON MODE RANGE (V)
–1.0
–1.5
±I
BIAS
(nA)
–2.0
I
SUPPLY
PER AMPLIFIER (mA)
Input Noise Spectral Density
100
T
A
= 25°C
V
S
=
±12V
I
S
PER AMPLIFIER = 10mA
e
n
100
OUTPUT SATURATION VOLTAGE (V)
INPUT VOLTAGE NOISE (V/√Hz)
10
I
SC
(mA)
1
i
n
0.1
1
10
100
1k
FREQUENCY (Hz)
10k
Open-Loop Gain and Phase
vs Frequency
120
100
80
60
GAIN (dB)
40
20
0
GAIN
T
A
= 25°C
V
S
=
±12V
A
V
= –10
R
L
= 100Ω
I
S
PER AMPLIFIER = 10mA
10M
1M
FREQUENCY (Hz)
100M
1739 G07
PHASE
–3dB BANDWIDTH (MHz)
30
25
20
15
10
5
0
2
4
6
8
10
12
14
SUPPLY CURRENT PER AMPLIFIER (mA)
1739 G08
–40
–80
–120
–160
–200
–240
–280
SLEW RATE (V/µs)
–20
–40
–60
–80
100k
4
U W
1739 G01
1739 G04
Input Common Mode Range
vs Supply Voltage
T
A
= 25°C
∆V
OS
> 1mV
200
Input Bias Current
vs Ambient Temperature
V
S
=
±12V
180 I
S
PER AMPLIFIER = 10mA
160
140
120
100
80
60
40
20
2.0
1.5
1.0
0.5
V
–
2
4
8
10
6
SUPPLY VOLTAGE (±V)
12
14
1739 G02
0
–50
–30
10
30
50
–10
TEMPERATURE (°C)
70
90
1739 G03
Output Short-Circuit Current
vs Ambient Temperature
800
780
V
S
=
±12V
I
S
PER AMPLIFIER = 10mA
V
+
–0.5
–1.0
–1.5
Output Saturation Voltage
vs Ambient Temperature
V
S
=
±12V
R
L
= 100Ω
I
LOAD
= 250mA
INPUT CURRENT NOISE (pA/√Hz)
PHASE (DEG)
760
740
720
700
680
660
640
620
SOURCING
SINKING
10
1
1.5
1.0
0.5
V
–
– 50 –30
–10
I
LOAD
= 250mA
R
L
= 100Ω
0.1
100k
600
–50
–30
30
–10 10
50
TEMPERATURE (°C)
70
90
50
30
10
TEMPERATURE (°C)
70
90
1739 G06
1739 G05
–3dB Bandwidth
vs Supply Current
120
80
40
0
Slew Rate vs Supply Current
1000
900
800
700
600
500
400
300
200
100
0
2 3 4 5 6 7 8 9 10 11 12 13 14 15
SUPPLY CURRENT PER AMPLIFIER (mA)
1739 G09
45
40
35
T
A
= 25°C
V
S
=
±12V
A
V
= 10
R
L
= 100Ω
T
A
= 25°C
V
S
=
±12V
A
V
= –10
R
L
= 1k
RISING
FALLING
1739fas, sn1739
LT1739
TYPICAL PERFOR A CE CHARACTERISTICS
CMRR vs Frequency
100
COMMON MODE REJECTION RATIO (dB)
90
80
70
60
50
40
30
20
10
0
0.1
POWER SUPPLY REJECTION (dB)
T
A
= 25°C
V
S
=
±12V
I
S
= 10mA PER AMPLIFIER
GAIN (dB)
1
10
FREQUENCY (MHz)
Output Impedance vs Frequency
1000
T
A
= 25°C
V
S
±12V
I
S
PER
AMPLIFIER = 2mA
10
I
S
PER
AMPLIFIER = 10mA
I
S
PER
AMPLIFIER = 15mA
I
SHDN
(mA)
2.5
SUPPLY CURRENT PER AMPLIFIER (mA)
100
OUTPUT IMPEDANCE (Ω)
1
0.1
0.01
0.01
0.1
1
10
FREQUENCY (MHz)
Differential Harmonic Distortion
vs Output Amplitude
f = 1MHz
T
A
= 25°C
–50 V
S
=
±12V
A
V
= 10
R
L
= 50Ω
–60 I PER AMPLIFIER = 10mA
S
HD3
–70
–80
HD2
–90
–100
0
2
4
6
8
10
12
14
16
18
V
OUT(P-P)
1739 G16
–40
DISTORTION (dBc)
DISTORTION (dBc)
U W
1739 G10
PSRR vs Frequency
100
90
80
70
60
50
40
30
20
10
0
100
Frequency Response
vs Supply Current
30
25
20
15
10
5
0
–5
–10
–15
–20
2mA PER AMPLIFIER
10mA PER AMPLIFIER
15mA PER AMPLIFIER
V
S
=
±12V
A
V
= 10
V
S
=
±12V
A
V
= 10
I
S
= 10mA PER AMPLIFIER
(–) SUPPLY
(+) SUPPLY
–10
0.01
0.1
1
10
FREQUENCY (MHz)
100
1739 G11
1k
10k
100k
1M
10M
FREQUENCY (Hz)
100M
1739 G12
I
SHDN
vs V
SHDN
35
T
A
= 25°C
V
S
=
±12V
V
SHDNREF
= 0V
30
25
20
15
10
5
0
Supply Current vs V
SHDN
T
A
= 25°C
V
S
=
±12V
V
SHDNREF
= 0V
2.0
1.5
1.0
0.5
100
1739 G13
0
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
V
SHDN
(V)
1739 G14
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
V
SHDN
(V)
1739 G14
Differential Harmonic Distortion
vs Frequency
–40
–45
–50
–55
–60
–65
–70
–75
–80
–85
HD2
HD3
V
O
= 10V
P-P
T
A
= 25°C
V
S
=
±12V
A
V
= 10
R
L
= 50Ω
I
S
PER AMPLIFIER = 10mA
–90
100 200 300 400 500 600 700 800 900 1000
FREQUENCY (kHz)
1739 G17
1739fas, sn1739
5
嵌入式系统
